Earth Origins Greenhouse

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Earth Origins Greenhouse - SHCS

The cycle of air moving though the greenhouse moves the energy from the sun into the air and then into the soil. Let's take a look at the cycle using some of the readings I've in this case: The air begins it journey at the blower intake at 80.9 deg F. and 44 % Relative Humidity (RH). It exits at the other end of the greenhouse, traversing the hundreds of feet of subterranean air tubes. Underground, the air cools because of exposure to massive amounts of subsoil, hopefully raising it's RH to Dewpoint (DP) - the point at which practically all of the heat energy is squeezed out and the vapor condenses completely. The air is then exposed to the sun, absorbs energy, drops to 27% RH ("dries out"), sucks up humidity from the plants, and returns to the blower re-charged at 44% RH and 80.9 deg F. In this case, however, the air exits at 67.3 deg F., RH at 57%, DP at 50.4 deg F. - only 16.9 deg from the magic temperature of DP. Although not optimal performance, the heat transfer is still proceeding. To optimize this greenhouse's performance, the dewpoint in the tubing has to be raised to the soil temperature. You do that by increasing the humidity and temperature in the greenhouse - watching the vents so excessive amounts of cooler, dry air isn't coming in from outside. That care of, the heat charging cycle dramatically improves, and the subsequent cooling effect of the SHCS improves. A win situation for the plants (higher RH and temp) and a win for heat storage. A win-win, because the heat storage is also the root zone for the plants!